高温管式炉煤粉燃烧NO排放规律研究

利用自制等温实验台炉模拟炉膛高温环境，研究了高温度1150～1550℃下煤粉燃烧特性，并同步测量了NO的生成量。结果表明：高温环境下煤粉燃烧可分为两个阶段，即挥发分和焦炭燃烧阶段。高温段显示提高温度可以较好地改善燃烧特性，同时温度由1150℃增加到1250℃时，燃烧失重速率增加幅度较其他温度区间大。NO瞬时排放浓度随燃烧经历了一个先增大后减小的过程，且峰值在燃烧过程前期。煤化程度越高，煤粉不能快速完成燃烧，焦炭中含N量大，释放缓慢，不能形成有效还原性气氛，使得总体NO排放较多。高温1550℃由空气产生的热力型NO高达3．5×10^-3mg／s。

Investigation on Combustion Characteristics and NO Emission of Pulverized Coal in High Temperature Tube Furnace

Abstract： The combustion characteristics of pulverized coal and synchronously NO releasing at 1 150 - 1 550℃ were studied by self-made bench which simulates the high-temperature atmosphere of furnace and achieves isothermal gravimetric measurement. The results show that at high temperature the combustion of pulverized coal can be divided into two stages which are the combustion of volatile and char. At high temperature, increasing temperature can improve combustion characteristics well. At the same time when the temperature changes from 1 150~C to t 250~C, the rate of weight loss is increased more than other same range. With burning NO instantaneous emission first increases and then decreases, and the peak is in the early stage of combustion. When the coal rank of pulverized coal is higher, it can burnout quickly, and char contains large amount of N. The char - N releases slowly and it cannot form the effective reducing atmosphere to make NO emissions more. At the temperature 1 550℃ the instantaneous mass of thermal - NO is up to 3. 5 × 10^-3mg/s. Keywords. tubular furnace; high-temperature ; combustion characteristics ; NO emissions